Myself and Daughter Number Four had to get her a small whiteboard for class. This isn’t a high-end piece of equipment, so we knew exactly where to go to get it. In the shopping centre near where we live, there are a number of shops that sell this kind of thing, all of which have unambiguous names like Low Pricez or Supercheapo!

Once we’d located the whiteboard, (€2.50), Daughter Number Four looked at me slyly and suggested: now, let’s go buy some stuff we don’t need.

She knows me so well.

What’s interesting about these kinds of shops is that you know exactly what they are, but you also don’t. Their singular pitch to the consumer is that they sell products cheaply; but other than that, they are uncategorisable, because they sell everything. And the nature of that stock can change with each visit.

They are marvellously random, and as such pose a range of existential questions to the consumer. Of course, you don’t need a canoe or a shortwave radio, but could these products alter the texture of your life? Once you’ve taken the necessary canoe lessons, could it profoundly change your relationship to nature? Think of it: every weekend, traversing the rivers and lakes of Ireland, finally in tune with the beating heart of our fair island. Perhaps you should also get a tent, so you can camp by the river bank. At night, you can look up at the stars and talk to your deserted family on the shortwave radio.

These products are not just things. They promise personal transformation, new skills, new sources of joy and convenience. It’s dizzying – and addictive.

While the random-product shops are a relatively recent development, the idea isn’t new: other supermarket chains have been offering random middle-aisle products for decades. You go in to buy milk, and you come home with a soldering kit. But you forget the milk. The random-product shops have simply inverted the model: you go in to buy the soldering kit, but also come home with four jars of marmalade.

There is the psychological stuff at work here: the haphazard, even slightly shambolic way the goods are displayed somehow reinforces the idea that there are genuine bargains to be had. It flatters us into thinking that we have embarked on a quest, and that our relentless aisle-prowling will be rewarded. Occasionally, it might be something we actually want. But the thrill of the search is such that we rarely consider the quality, where it’s been made, or under what circumstances.

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Most of the time though, what’s on offer are things we didn’t know we needed until we saw them: kitchen gizmos solving problems we didn’t know we had. Space-age gardening tools and implements for drilling holes in space. And once discovered, there’s simply no time to consider whether this diagnostic car scanner is cheaper than one you might get elsewhere.

Anyway, you’ve never seen one before, so you wouldn’t know where to go to make that comparison. It also looks cool with all the buttons and lights, and you’re bound to save money not having to bring the car to the garage.

You know what happens next. The thing breaks after the third time you use it. Or it doesn’t work that well. Or the instructions are in Hindi. It ends up in a cupboard, along with all the other rubbish you’ve bought.

No judgment from me: I’ve been that sucker. I have tools and drill bits and electronic yokes that barely made it out of the box before falling into disuse.

Yet despite that, when Daughter Number Four invited me to buy stuff I don’t need, I still walked around the shop with her. You never know. But I decided that I’m not going to take up tennis and I don’t need another meat thermometer. My life is fine as it is. Instead, I got some biscuits.